1. Technical Field
The present invention relates generally to an evolved gas analyzer and a method for analyzing evolved gas, the method analyzing gas components evolved by heating a sample, thereby identifying, quantifying, etc. the sample.
2. Description of the Related Art
In order to increase flexibility of resins, plasticizers such as phtalates, etc. are added to the resins. After 2019, four substances of the phtalates will be restricted under the restriction of hazardous substances directive (RoHS). Therefore, it is required to identify and quantify the phtalates in the resins.
The phtalates are volatile substances such that a conventional evolved gas analysis (EGA) is applied to analyze the phtalates. The EGA is a method used to analyze gas components evolved by heating a sample by using a gas chromatograph or using various analyzers applying mass spectrometry, etc.
In an evolved gas analysis, a sample is placed on a sample stage, and the sample is heated by the sample stage in a heating furnace. Alternatively, the sample is set on a holding tool, and the holding tool is inserted into the heating furnace to evolve a gas component for the analysis. In addition, after the analysis, the sample stage is naturally cooled to a room temperature, and the sample is changed and is heated from about the room temperature to start a next analysis. However, standby time to cool the sample stage is long, and thus, work efficiency of the entire analysis process is reduced.
Therefore, technology of cooling air in the heating furnace by flowing refrigerant gas through a duct positioned in the heating furnace is disclosed in Patent Document 1. Technology of bring a cooling device into contact with a sample stage in a vacuum chamber, which is a heating furnace, is disclosed in Patent Document 2.